Azido polymers find use as energetic binders in a variety of composite explosive and propellant applications, but few azido polyesters have previously been reported: a method is introduced for the preparation of two azido polycarbonates, poly(2,2'-bisazidomethyl-1,3-propyl carbonate) and poly(3-azido-1,2-propyl carbonate), possible binder candidates for energetics applications. The preparation method for these polymers involves a two-step synthesis starting from the bulk polymerization of the commercially sourced diols with diphenyl carbonate in the presence of lanthanum (III) acetylacetonate as a neutral catalyst, and subsequent azidation in cyclohexanone. The physical and thermal characteristics of each are reported, indicating properties similar to other azido-polymers. The thermal and mechanical properties of cured azido polyester resin mixtures are the subject of ongoing research.